<form class="form">
  <header>
    Credit card information
  <span class="message">Fill the form to continue.</span>
  </header>
  <label>
    <span>Card Number</span>
    <input placeholder="Type your card number" class="input" type="number" required="">
  </label>
  <label>
    <span>Name on card</span>
    <input placeholder="Type your name as appear on card" class="input" type="text" required="">
  </label>
  <fieldset>
    <label class="sm">
    <span>Exp. Month</span>
    <div class="custom-select">
    <select class="input" type="select" required="">
      <option></option>
      <option>January</option>
      <option>February</option>
      <option>March</option>
      <option>April</option>
      <option>May</option>
      <option>June</option>
      <option>July</option>
      <option>August</option>
      <option>September</option>
      <option>October</option>
      <option>November</option>
      <option>Dicember</option>
    </select>
    </div>
  </label>
  <label class="sm">
    <span>Exp. Year </span>
    <div class="custom-select">
    <select class="input" type="select" required="">
      <option></option>
      <option>2023</option>
      <option>2024</option>
      <option>2025</option>
      <option>2026</option>

    </select>
    </div>
  </label>
    <label class="sm">
    <span>CW </span>   
    <input class="input" placeholder="1234" size="4" maxlength="4" type="text" required="">
  </label>
  </fieldset>
  <div class="submitCard">
    <button>Complete payment</button>
  </div>
</form>
<style>
/* From Uiverse.io by roroland - Tags: form */
/* Initial form state */
.form {
  --col1: #fff;
  --col2: #252325;
  --col3: rgba(232, 213, 196, 0.9);
  --col4: #ffffff;
  --col5: #683363;
  --sh: rgba(80, 80, 80, 0.35);
  --rad: 4px;
  --radBig: 10px;
  border-radius: 0 0 var(--radBig) var(--radBig);
  box-shadow: 0 0 20px var(--sh);
  display: flex;
  flex-direction: column;
  gap: 1.5em 1em;
  padding: 1em;
  position: relative;
  max-width: 75%;
  max-height: 90px;
  transition: background .3s ease-out, max-height .3s ease-out;
  overflow: hidden;
}

.form::before {
  content: 'Ready to purchase?';
  color: var(--col2);
  font-size: 1.2em;
  font-weight: 700;
  display: grid;
  width: calc(100% - 2em);
  height: 60%;
  position: absolute;
  place-items: center;
  z-index: 99999;
}

.form::after {
  content: '';
  backdrop-filter: blur(6px) grayscale(100%);
  background: linear-gradient(-180deg, rgba(255,255,255,1) 0%, rgba(255,255,255,.5) 70%, rgba(255, 255, 255, 0.3) 90%);
  height: 100%;
  width: 100%;
  left: 0;
  top: 0;
  display: block;
  position: absolute;
  z-index: 999;
}

.form::after,
.form::before {
  border-radius: 0 0 var(--radBig) var(--radBig);
  pointer-events: none;
  transition: all .5s ease-out;
}

/* Form hover and focus */
.form:hover,
.form:focus-within {
  max-width: 100%;
  max-height: 380px;
}

.form:focus-within {
  overflow: initial;
}

.form:hover::before,
.form:hover::after {
  opacity: 0;
}

.form:hover::after {
  backdrop-filter: blur(0) grayscale(0%);
}

.form header {
  color: var(--col1);
  font-size: 1.25rem;
  font-weight: 600;
}
/* Labels and inputs UI */
:is(.form) label span, label input {
  flex: 1 100%;
  transition: all .3s ease-out;
}

:is(.form) input, select, button {
  appearance: none;
  border: 0;
  padding: .75em;
  border-radius: var(--rad);
  transition: all .3s ease-out;
}

.form label {
  display: flex;
  flex-flow: row wrap;
  color: var(--col4);
  gap: .5em;
}

.form input {
  box-shadow: inset 3px 3px 1px var(--sh);
}

.form fieldset {
  display: flex;
  backdrop-filter: blur(10px);
  flex-flow: row nowrap;
  gap: 1em;
  position: relative;
  transition: all .3s ease-out;
  padding: 1rem;
  z-index: 10;
  border: 3px double var(--col1);
  border-radius: var(--rad);
}

.form fieldset label {
  flex: 1;
  display: flex;
  flex-flow: row wrap;
  font-size: .75em;
}

.sm {
  justify-content: space-around;
}

.sm span {
  text-align: center;
}

.form select {
  box-shadow: inset 3px 3px 1px var(--sh);
  padding: .75em 1.75em .75em 0.5em;
  position: relative;
}

.custom-select {
  position: relative;
}

.custom-select::after {
  position: absolute;
  content: "";
  top: 45%;
  right: 5px;
  width: 0;
  height: 0;
  border: 6px solid transparent;
  border-color: var(--col5) transparent transparent transparent;
}

.form fieldset span {
  flex: 1 100%;
}

.form fieldset input {
  flex: 0 1 40px;
}

.form button {
  background-color: var(--col1);
  color: var(--col4);
  border: 2px solid var(--col4);
  font-size: 1em;
  font-weight: 700;
  align-self: center;
  padding: .5em 1.5em;
  appearance: none;
}

/* Form and UI valid and invalid states */
.form input:focus,
.form select:focus {
  outline: 3px solid var(--col3);
  outline-offset: 1px;
}

.form input:invalid:not(:focus),
.form select:invalid:not(:focus) {
  background-color: var(--col3);
  outline: 3px solid var(--col4);
  outline-offset: 1px;
}

.form input:valid:not(:focus),
.form select:valid:not(:focus) {
  outline: 3px solid var(--col1);
  outline-offset: 1px;
}

.form .message {
  display: block;
  opacity: 0;
  font-size: .75em;
  font-weight: 400;
  transition: all .3s ease-out;
  margin: -1rem 0 0;
}

.form:has(:invalid) .message {
  opacity: 1;
  margin: .25rem 0 0 0;
}

label:has(input:invalid),
label:has(select:invalid) {
  color: var(--col3);
  opacity: .8;
}

label:has(input:valid),
label:has(select:valid) {
  opacity: 1;
}

.form:hover:has(:focus, :active):valid .submitCard {
  max-height: 180px;
  opacity: 1;
  transition: opacity 1s ease-out .5s, translate 1.3s ease-out;
  translate: 0 100%;
}

.form:hover:invalid {
  transition: all .3s ease-out;
  background-color: var(--col5);
}

.form:hover:valid {
  transition: all .3s ease-out;
  background-color: var(--col1);
}

.form:hover:valid * {
  color: var(--col2);
}

.form:hover:valid input,
.form:hover:valid select {
  outline: 3px solid var(--col2);
}

.form:hover:invalid fieldset {
  border: 1px dashed var(--col3);
}

.form:hover:valid fieldset {
  border: 1px dashed var(--col2);
}

/* Submit block */
.form .submitCard {
  display: flex;
  justify-content: center;
  background-color: var(--col2);
  border-radius: 0 0 var(--rad) var(--rad);
  bottom: 0;
  padding: .5em;
  opacity: 0;
  max-height: 0;
  translate: 0 -100%;
  position: absolute;
  width: calc(100% - 2em);
  transition: all .5s ease-out .1s;
  z-index: -1;
}
</style>
